What is sibling rivalry?

0:00 Welcome to Philosophy is not boring by kidopoly.com. I'm Mira. And I'm Finn. Before we start, we have a massive shout-out to brothers Nathan and Maxie. They sent us a brilliant question about something I think everyone with a brother or sister wonders about.

0:18 Yeah, they asked, why does it feel like your brother is always the annoying one?

0:24 It is such a good question, Nathan and Maxie, and it is exactly what we are exploring today. If you haven't already, tap follow wherever you're listening so you never miss an episode.

0:36 Okay, but seriously, why is it that a joke your best friend makes is hilarious? But if your brother makes the exact same joke, you just want to scream.

0:46 Or the way they chew their food? Or when you call dibs on the front seat of the car and they just sprint past you and lock the door.

0:53 Ugh yes. Or when they just look at you with that face. You know the exact face I mean. It feels like they are professionally trained in making us mad.

1:03 Philosophy is a big word, but really it just means wondering about things. And today, we are wondering about something that happens in almost every house in the world.

1:14 So we are asking a huge question. Why do the people we live with drive us the craziest? And is there a secret psychological reason behind all those arguments?

1:24 Let's start with the basics. Sharing a home means sharing a lot of things. You share your toys, you share your living space, and most importantly, you share your parents' attention.

1:36 So it's basically a competition. Like we are all playing a game of who gets the most stuff. Exactly.

1:43 In family psychology, this is called natural rivalry. Think about human history. Thousands of years ago, if a kid didn't get enough food, warmth, or protection from their parents, they literally wouldn't survive.

1:57 Wait, so getting your parents' attention was a matter of life and death?

2:02 Yes. The kids who were loud and demanded attention got what they needed. So our brains evolved to be very sensitive to fairness and making sure we get our share.

2:13 That makes total sense. If my brother gets an extra scoop of ice cream, my brain acts like it is a major disaster.

2:21 It really does. But to truly understand why siblings know exactly how to annoy each other, we need to meet a famous developmental psychologist named Judy Dunn. Who is Judy Dunn? She is a brilliant British researcher. Back in the 1980s, psychologists used to study kids mostly in quiet, boring laboratories.

2:43 They would bring kids into a weird room and try to test them.

2:46 But kids don't act normal in a lab. They act normal in their living rooms when nobody is watching.

2:52 That is exactly what Judy Dunn thought. So she actually went into people's homes to observe toddlers and older siblings playing, fighting, and just living together.

3:04 Oh wow, she must have seen a whole lot of arguments.

3:07 She definitely did. But she also noticed something huge: a discovery that changed how we see sibling fights forever. Before Judy Dunn did her research, many psychologists believed that very young kids, like toddlers, didn't really understand other people's feelings yet.

3:25 Wait, they thought little kids were just totally oblivious.

3:29 Yeah, they thought kids under four were mostly ego-centric, which means they only cared about themselves and couldn't understand that other people had different thoughts in their heads.

3:39 But Judy Dunn said, no way. Just look at how they act at home.

3:44 Right. She listened to the way two-year-olds joked, argued, and talked about feelings with their mothers and older siblings. She realised they were actually little emotional geniuses. Emotional geniuses? What does that mean? It means siblings actually figure out each other's feelings incredibly early.

4:04 Because you live together, you learn to read your siblings' mind way before you understand anyone else's. Hold on.

4:11 If my brother understands my feelings so well, why does he do the exact thing that makes me mad?

4:18 Okay, here is the genius part. Because they understand your feelings so well, they know exactly which buttons to push. No way! They do it on purpose. Yes, think about it as a thought experiment. Imagine you have a favourite toy car and a random kid at the playground takes it.

4:38 Okay, they probably just took it because it looked shiny. They have no idea it is my absolute favourite.

4:45 Right, but if your sibling takes it, they know it is your favourite. They know exactly how much it means to you, and they use that information to get a reaction out of you.

4:55 Wait, so my sibling being super annoying is actually a sign that they have really good emotional intelligence. Pretty much.

5:04 To be a really good annoyer, you actually have to be a really good mind reader. And there is another piece to the puzzle of why siblings drive us crazy. It is something psychologists call a social allergy.

5:17 A social allergy? That sounds like a fancy science term. What is it?

5:23 It means that when you do something every single day with someone, their tiny normal habits get magnified in your brain. You become hyper-aware of them because you are exposed to them so often.

5:36 Like how my brother always taps his foot when he reads. At first it was fine, but now it sounds like a giant drum in my head.

5:45 Exactly! It's like eating your favourite pizza every single day. Eventually, you might get totally sick of it, and you'll start noticing every single tiny burnt piece of crust. Your brain is so used to your sibling that the volume gets turned way up on the tiny things.

6:03 Oh, so because I am with my brother every single day, I notice every single weird thing he does. But wait, if he knows exactly what makes me mad, what else does he know?

6:14 That is the best part. Judy Dunn's research showed that this same mind-reading superpower means siblings can comfort each other better than almost anyone else. Because they know exactly what makes me happy too. Exactly. They know when you are faking being okay, and they know what actually cheers you up.

6:34 They learn empathy, which is the ability to understand how someone else feels, faster than kids without siblings.

6:42 Okay, that is true. But it still doesn't seem fair sometimes. Like, why do we have to fight so much?

6:49 That is where boundaries come in. Just because we have natural rivalry doesn't mean we have to be mean. We have to learn to set rules. Saying, I need some space right now, is a healthy way of protecting your relationship.

7:03 So, the fighting is natural, but we still have to choose how to handle it. Practising taking their perspective might actually help turn an annoying brother into a lifelong ally.

7:13 So, Nathan and Maxi, the next time your brother does that one tiny thing that drives you totally bananas, here is how you can look at it.

7:23 First, remind yourself it is just a social allergy. Your brain is playing a trick on you, making a tiny annoying habit seem huge just because you see it every day.

7:35 And second, remember that the reason they know exactly how to bug you is because you two are deeply emotionally connected. That same button-pushing superpower is what makes them understand you better than anyone else.

7:49 That is actually really cool. It kind of makes me respect the annoyingness. Just a little bit though.

7:56 Well, before you respect it too much, let's look at some wild fun facts. Did you know people have been arguing about sibling rivalry for literally thousands of years? Really? Like in ancient history? Yep. Some of the oldest stories in the world are basically giant sibling fights. In ancient myths, from the Egyptian story of Osiris and Set to the Greek gods, siblings are constantly tricking each other and arguing over who gets to rule the world.

8:28 So I guess arguing over who gets to hold the TV remote isn't so bad compared to arguing over who gets to rule the universe.

8:35 Not at all. And let's look at the animals. Some baby birds, like egrets, will actually push their siblings right out of the nest to get all the food. And baby piglets have special teeth just to fight their brothers and sisters for the best spot to drink milk.

8:52 Whoa, okay, suddenly my brother tapping his foot doesn't seem so bad. At least we aren't wild baby birds fighting in a tree.

9:00 Exactly. Human siblings just use words instead, which is definitely a step up. Alright, Finn, time for the quiz.

9:08 Are you ready? Okay, I'm ready. I hope I remember all the psychology terms. First question.

9:15 What is the name of the British psychologist who famously studied siblings? Next one. What do psychologists call it when tiny habits get magnified in your brain because you see someone every day? Question 3. According to the research, why siblings so good at knowing how to annoy you? Here's number four.

9:46 What were kids in ancient times and today naturally competing for in the house, besides toys in space? Last question. Where did the researcher go to observe how kids really acted instead of a boring laboratory? Great job! Let's see how you did. The first answer is Judy Dunn! For question two, that is called a social allergy.

10:18 Number three, the answer is because they figure out your feelings early and know exactly which buttons to push. Question four, they were competing for their parents' attention and resources. And the final answer is she studied them right in their own homes.

10:36 You know, thinking about all this actually helps. I think I'll be a tiny bit more patient the next time my brother is being a pest.

10:44 We will see about that. But it is really cool to know that even our fights are just a way of figuring each other out and building emotional intelligence.

10:54 Yeah, they really are. And hey, if you learned something new today about why siblings fight, please leave us a five-star review. Just scroll down and tap the stars.

11:05 And be sure to follow this show and check out our sister shows. History and science is not boring, and maths is not boring. Go give those a listen and a follow as well.

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11:20 See you next time on Philosophy is not boring. Bye.